SELECTED PAPERS 

 TABLE I 



Various types of oxidative glucose dissimilation by micro-organisms 

 i. C 6 H 12 6 + 60 2 -> 6C0 2 +6H 2 



carbon dioxide 



2. G 6 H 12 6 + 50 2 ->2HOOC-COOH+2C0 2 +4H a O 



oxalic acid 



3. CeH^Oe+iVaOa-* HOOC-CH 2 CCOOH+C0 2 +3H 2 



itaconic acid 



CH 2 



4. C 6 H 12 6 +iV 2 2 -^ HOOCCH 2 COH-CH 2 -COOH+ 2 H 2 



citric acid 



COOH 



5. C 6 H 12 6 + 2 -> CH 2 OH • CO • CHOH • CHOH • CHOH • COOH+H 2 



5-ketogluconic acid 



6. C 6 H 12 6 + 7 2 2 ->CH 2 OH- CHOH -CHOH -CHOH- CHOH -COOH 



gluconic acid 



7. C 6 H 12 6 + 1 /20 2 ^CH 2 OH-C = CH-CO-COH = CH+3H 2 



O 



kojic acid 



ous species are not at all confined to the use of glucose or related car- 

 bohydrates as a respiratory substrate. On the contrary it has been 

 established that representatives of very different groups of organic 

 compounds can be used as the sole source of carbon for special types 

 of aerobic bacteria, which implies that these bacteria can satisfy their 

 energy demand from an oxidation of the compounds in question. 

 Amongst these compounds are fatty acids, dicarboxylic acids, hy- 

 droxy-, keto- and amino-acids, but also aliphatic amines, various 

 aromatic compounds, sterols, hydrocarbons etc. Table II gives some 

 idea of the surprising diversity of substrates which can be used by one 

 and the same bacterial species. 



The bacterial world still has several other surprises for the student 

 of comparative physiology. To the genius of Winogradsky we owe the 

 knowledge that representatives of various bacterial groups can thrive 

 in the complete absence of all organic compounds, provided that 

 carbon dioxide is supplied together with some oxidizable inorganic 

 compound. Various types of such autotrophic bacteria have succes- 

 sively been discovered: the so-called nitrifying bacteria which oxidize 

 either ammonia or nitrite, the sulphur bacteria which oxidize hydro- 

 gen sulphide, elementary sulphur and some simple sulphur com- 



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